Semiconductor light-emitting device

ABSTRACT

A semiconductor light-emitting device comprises a semiconductor stack having a first surface, wherein the first surface comprises multiple protrusion portions and multiple concave portions; a first electrode on the first surface and electrically connecting with the semiconductor stack; a second electrode on the first surface and electrically connecting with the semiconductor stack; and a transparent conduction layer conformally covering the first surface and between the first electrode and the semiconductor stack, wherein the first electrode comprises a first bonding portion and a first extending portion, and the first extending portion is between the first bonding portion and the transparent conduction layer and conformally covers the transparent conduction layer.

RELATED APPLICATION DATA

This application is continuation application of U.S. patent applicationSer. No. 14/546,571, filed on Nov. 18, 2014, which claims the right ofpriority of TW Application No. 102141996, filed on Nov. 18, 2013, andthe content of which is hereby incorporated by reference in itsentirety.

TECHNICAL FIELD

The application is related to a structure of a semiconductorlight-emitting device.

DESCRIPTION OF BACKGROUND ART

Light-emitting diode (LED) has been applied to the optical displaydevice, traffic signs, data storage device, communication device,lighting device and medical equipment. As FIG. 5 shows, LED comprises ann-type semiconductor layer 1104, an active layer 1106, and a p-typesemiconductor layer 1108 sequentially formed on a substrate 1102, and aportion of the p-type semiconductor layer 1108 and the active layer 1106is removed to expose a portion of the n-type semiconductor layer 1104. Ap-type electrode a1 and an n-type electrode a2 are respectively formedon the p-type semiconductor layer 1108 and the n-type semiconductorlayer 1104. The n-type electrode a2 needs sufficient area for subsequentprocesses, such as wiring, so a considerable portion of the active layer1106 is removed, which leads to the drop of the light-emittingefficiency.

Besides, the above-mentioned LED can be further connected to otherdevice to form a light-emitting apparatus. FIG. 6 shows a structure of aconventional light-emitting apparatus. As FIG. 6 shows, a light-emittingapparatus comprises a sub-mount 1202 having one circuit 1204; one solder1206 on the sub-mount 1202 for fixing a LED 1210 on the sub-mount 1202and forming an electrical connection between the substrate 1212 of theLED 1210 and the circuit 1204 of the sub-mount 1202; and an electricalconnecting structure 1208 for electrically connecting the electrode 1214of the LED 1210 and the circuit 1204 of the sub-mount 1202, wherein theabove-mentioned sub-mount 1202 can be lead frame or large size mountingsubstrate for designing the circuit of the light-emitting apparatus andimproving heat dissipation efficiency.

SUMMARY OF THE DISCLOSURE

A semiconductor light-emitting device comprises a semiconductor stackhaving a first surface, wherein the first surface comprises multipleprotrusion portions and multiple concave portions; a first electrode onthe first surface and electrically connecting with the semiconductorstack; a second electrode on the first surface and electricallyconnecting with the semiconductor stack; and a transparent conductionlayer conformally covering the first surface and between the firstelectrode and the semiconductor stack, wherein the first electrodecomprises a first bonding portion and a first extending portion, and thefirst extending portion is between the first bonding portion and thetransparent conduction layer and conformally covers the transparentconduction layer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A shows a structure of a semiconductor light-emitting device I inaccordance with the first embodiment of the application;

FIG. 1B shows a top view of the structure of the semiconductorlight-emitting device I in accordance with the first embodiment;

FIG. 2 shows a structure of a semiconductor light-emitting device II inaccordance with the second embodiment of the application;

FIG. 3 shows a structure of a semiconductor light-emitting device III inaccordance with the third embodiment of the application;

FIGS. 4A to 4D show the process flow of the semiconductor light-emittingdevice in accordance with a process embodiment of the application;

FIG. 5 shows a cross-sectional view of a conventional LED structure;

FIG. 6 shows a structure of a conventional light-emitting apparatus;

FIG. 7 shows a structure in accordance with another embodiment of theapplication;

FIG. 8A shows a structure of a semiconductor light-emitting device IV inaccordance with the fourth embodiment of the application

FIG. 8B shows the top-view of the structure of the semiconductorlight-emitting device IV in accordance with the fourth embodiment of theapplication.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS First Embodiment

FIG. 1A shows a structure of a semiconductor light-emitting device I inaccordance with the first embodiment of the application. Thesemiconductor light-emitting device disclosed by the embodiment is aflip-chip type of light-emitting diode device with a concave reflector.The semiconductor light-emitting device comprises a semiconductor stack1 having a first surface 13 and a second surface 14 opposite to thefirst surface 13. The semiconductor stack 1 comprises a firstsemiconductor layer 11, a second semiconductor layer 12, and an activelayer 10 between the first semiconductor layer 11 and the secondsemiconductor layer 12, wherein the first surface 13 is the surface ofthe first semiconductor layer 11 and the second surface 14 is thesurface of the second semiconductor layer 12. The first semiconductorlayer 11 and the second semiconductor layer 12 have differentelectrically conductive types, electrical properties, polarities orprovide electric holes or electrons by being doped with differentelements; the active layer 10 between the first semiconductor layer 11and the second semiconductor layer 12 is capable of transformingelectrical energy into light energy. The wavelength of the light fromthe active layer 10 can be adjusted by changing the physical andchemical composition of one or multiple layers of the semiconductorstack 1. The commonly used material for forming the semiconductor stack1 comprises aluminum gallium indium phosphide (AlGaInP) series, aluminumgallium indium nitride (AlGaInN) or zinc oxide (ZnO) series. The activelayer 10 can be a single heterostructure (SH), double heterostructure(DH), double-side double heterostructure (DDH), multi-quantum well (MWQ)structure. Specifically, the active layer 10 can be intrinsic, p-type,or n-type semiconductor. When the electrical current flows through thesemiconductor stack 1, the active layer 10 is capable of emitting light.As the material of the active layer 10 is aluminum gallium indiumphosphide (AlGaInP) series, the active layer 10 is capable of emittingred, orange, yellow or amber light; as the material of the active layer10 is aluminum gallium indium nitride (AlGaInN), the active layer 10 iscapable of emitting blue or green light. In the following embodiments,the material of the active layer 10 is aluminum gallium indium phosphide(AlGaInP) series.

The first surface 13 of the semiconductor stack 1 has multipleprotrusion portions 131 and multiple concave portions 132 alternatelyarranged, and each of the multiple protrusion portions 131 comprises aplateau 1313 and at least one bevel 1312, wherein an inclined angle θbetween 15 and 75 degrees is formed between the bevel 1312 and thebottom surface of the concave portion 132, and each of the multipleprotrusion portions 131 has a height between 500 nm and 5000 nm relativeto the concave portion 132. On each of the plateaus 1313, there is atleast one contacting structure 2 arranged for ohmically contacting thefirst semiconductor layer 11. In the embodiment, the material of thecontacting structure 2 comprises Ge, Be, Au, Ni, Pd, Zn or the alloythereof.

A transparent conduction layer 3 conformally covers the first surface 13and electrically contacts the contacting structure 2. The material ofthe transparent conduction layer 3 comprises ITO, InO, SnO, CTO, ATO,AZO, ZTO, ZnO, or GaP.

A first electrode 4 is formed on the first surface 13. The firstelectrode 4 comprises a first extending portion 41, a first bondingportion 43, and a first connecting portion 42. The first connectingportion 42 is formed on a first side 15 of the semiconductor stack 1 forconnecting the first extending portion 41 and the first bonding portion43, wherein the first extending portion 41 conformally covers andohmically contacts the transparent conduction layer 3. Because the firstextending portion 41 conformally covers the transparent conduction layer3, the first extending portion 41 has a concave-convex surface 410. Thefirst extending portion 41 is made of metal with high reflectivity forreflecting the light emitted from the active layer 10 to exit from thesecond surface 14, and meanwhile, the concave-convex surface 410 is ableto concentrate the reflected light along the vertical direction H. Afirst insulating layer 61 is formed between the first extending portion41 and the first bonding portion 43, covers the first extending portion41, and extends to cover a second side 16 of the semiconductor stack 1.The first insulating layer 61 fills the concave-convex surface 411 ofthe first extending portion 41, wherein the concave-convex surface 411is formed by the first extending portion 41 being conformal to the firstsurface 13. The material of the first bonding portion 43 and the firstconnecting portion 42 is different from the material of the firstextending portion 41. The material of the first bonding portion 43 andthe first connecting portion 42 comprises Ti, W, Pt, Ni, Sn, Au or thealloy thereof; the first extending portion 41 comprises metals with highreflectivity, such as Ag, Au, Al, Ni, Sn, Cu, Ti, Pt, stacks thereof orthe alloy thereof; the material of first insulating layer 61 comprisesorganic material, such as Sub, BCB, PFCB, epoxy, acrylic resin, COC,PMMA, PET, PC, polyetherimide and Fluorocarbon Polymer, inorganicmaterial, such as silicone and glass, or dielectric material, such asAl₂O₃, SiNx, SiO₂, TiO₂ and MgF₂.

A second electrode 5 comprises a second extending portion 51 on thesecond surface 14, a second bonding portion 53 on the first surface 13,and a second connecting portion 52 on the second side 16 of thesemiconductor stack 1 for connecting the second extending portion 51 andthe second bonding portion 53. The second surface 14 of thesemiconductor stack 1 has multiple recesses 141, wherein the multiplerecesses 141 are corresponding to the multiple concave portions 132 ofthe first surface 13 in the vertical direction H. The second extendingportion 51 is disposed in the multiple recesses 141 to ohmically contactthe second semiconductor layer 12, and the second bonding portion 53 ison the first surface 13 and isolated from the first extending portion 41and the transparent conduction layer 3 by the first insulating layer 61.There is a gap 7 between the second bonding portion 53 and the firstbonding portion 43 to separate second bonding portion 53 and the firstbonding portion 43, wherein the width of the gap 7 is between 70 μm and250 μm. As the shape of the semiconductor light-emitting device is asquare with four 12 mil sides and the area of the semiconductorlight-emitting device is 144 square mil, the total area of the firstbonding portion 43 and the second bonding portion 53 is between 15%˜80%of the area of the semiconductor light-emitting device, and, in otherwords, the area of the first bonding portion 43 and the second bondingportion 53 is between 21.6 and 115.2 square mil. As the shape of thesemiconductor light-emitting device is a square with four 28 mil sidesand the area of the semiconductor light-emitting device is 784 squaremil, the total area of the first bonding portion 43 and the secondbonding portion 53 is between 60%˜92% of the area of the semiconductorlight-emitting device, and, in other words, the total area of the firstbonding portion 43 and the second bonding portion 53 is between 470.4and 721.28 square mil. As the shape of the semiconductor light-emittingdevice is a square with four 40 mil sides and the area of thesemiconductor light-emitting device is 1600 square mil, the total areaof the first bonding portion 43 and the second bonding portion 53 isbetween 75%˜95% of the area of the semiconductor light-emitting device,and, in other words, the total area of the first bonding portion 43 andthe second bonding portion 53 is between 900 and 1520 square mil. Thesecond connecting portion 52 is on the second side 16 of thesemiconductor stack 1 and isolated from the second side 16 by the firstinsulating layer 61. As FIG. 1B shows a top view of the structure of thesemiconductor light-emitting device I in accordance with the firstembodiment, the second extending portion 51 comprises multiple firstextending electrodes 511 which are parallel to each other and a secondextending electrode 512. The second extending electrode 512 isperpendicular to the multiple first extending electrodes 511 andelectrically connects with the second connecting portions 52 arranged inthe corner 18 and the corner 19 of the semiconductor stack 1. The secondextending electrode 512 is near and parallel to a side 17 of thesemiconductor stack 1, and the second extending electrode 512 and themultiple first extending electrodes 511 do not overlap with all of thecontacting structures 2 in the vertical direction H. The material of thesecond extending portion 51 comprises metal, such as Au, Ge, Be, Ni, Pd,Zn or the alloy thereof, or transparent oxide, such as ITO, InO, SnO,CTO, ATO, AZO, ZTO or ZnO; the material of the second bonding portion 53and the second connecting portions 52 comprises Ti, W, Pt, Ni, Sn, Au orthe alloy thereof.

An adhesive layer 9 covers the second surface 14, the second extendingportion 51, and the second connecting portions 52. A substrate 8 isadhered to the second surface 14 by using the adhesive layer 9, and thelight emitted from the active layer 10 is able to penetrate thesubstrate 8 and the adhesive layer 9. The material of the adhesive layer9, which is transparent to the light emitted from the active layer 10,comprises organic material, such as Sub, BCB, PFCB, epoxy, acrylicresin, COC, PMMA, PET, PC, polyetherimide and Fluorocarbon Polymer,inorganic material, such as silicone and glass, or dielectric material,such as Al₂O₃, SiNx, SiO₂, TiO₂ and MgF₂. The material of the substrate8, which is transparent to the light emitted from the active layer 10,comprises GaAs, GaP, GaN, sapphire, diamond, glass, quartz, acryl, ZnOor MN.

In another embodiment, a transparent conductive layer (not shown) can bearranged between the adhesive layer 9 and the second surface 14 andelectrically connects with the second semiconductor layer 12 and thesecond extending portion 51 for improving electrical current spreadingtransversely so the area of the second extending portion 51 is reduced,or can even replace the second extending portion 51 to reduce theshading area of the second extending portion 51 and increase the lightextracting efficiency. The material of the transparent conductive layercomprises ITO, InO, IZO, SnO, CTO, ATO, AZO, ZTO, ZnO, or GaP.

Second Embodiment

FIG. 2 shows a structure of a semiconductor light-emitting device II inaccordance with the second embodiment of the application. The differencebetween the structure of the semiconductor light-emitting device IIdisclosed in the second embodiment and the structure of thesemiconductor light-emitting device I disclosed in the first embodimentis that the structure of the semiconductor light-emitting device II hasa transparent layer 31 between the transparent conduction layer 3 andthe first surface 13. The transparent layer 31 conformally covers thefirst surface 13 and exposes the contacting structure 2 so thecontacting structure 2 directly contacts with the transparent conductionlayer 3. The refractive index of the transparent layer 31 is smallerthan the refractive index of the transparent conduction layer 3, and,preferably, the refractive index of the transparent layer 31 is smallerthan 1.5 so that the reflectivity to the light emitted from the activelayer 10 can be increased. The material of the transparent layer 31comprises transparent inorganic material, such as SiO_(x), SiN_(x) andMgF₂, or transparent organic material, such as silicone, epoxy,polyimide, or PFCB.

Third Embodiment

FIG. 3 shows a structure of a semiconductor light-emitting device III inaccordance with the third embodiment of the application. The differencebetween the structure of the semiconductor light-emitting device IIIdisclosed in the third embodiment and the structure of the semiconductorlight-emitting device I disclosed in the first embodiment is that, inthe semiconductor light-emitting device III, a transparent layer 31contacts the first extending portion 41 and the first surface 13 andexposes the contacting structure 2 so that the contacting structure 2directly connects with the first extending portion 41 and the electricalcurrent flowing through the semiconductor stack 1 enters the firstextending portion 41 via the contacting structure 2. The material of thetransparent layer 31 as mentioned in the third embodiment comprisestransparent inorganic material, such as SiOx, SiNx and MgF₂, ortransparent organic material, such as silicone, epoxy, polyimide orPFCB.

Process Embodiment

FIGS. 4A to 4D show the process flow of the semiconductor light-emittingdevice in accordance with process embodiment of the application. As FIG.4A shows, a growth substrate 81 is provided, and a semiconductor stack1, which is formed on the growth substrate 81, comprises a firstsemiconductor layer 11, an active layer 10, and a second semiconductorlayer 12, wherein the material of the first semiconductor layer 11, theactive layer 10, and the second semiconductor layer 12 is the same asthe material mentioned in the first embodiment, and the material of thegrowth substrate 81 comprises sapphire, SiC, GaN, GaAs or GaP. Multiplerecesses 141 are formed on a second surface 14 of the secondsemiconductor layer 12 by lithography etching method which comprises dryetch and wet etch, wherein the multiple recesses 141 on the secondsurface 14 are connected. The next step is to form a second extendingportion 51 in the multiple recesses 141 by evaporation, wherein thematerial of the second extending portion 51 comprises Au, Ge, Be, Ni,Pd, Zn or the alloy thereof.

As FIG. 4B shows, a substrate 8 is provided to be adhered to the secondsurface 14 with an adhesive layer 9 by the use of bonding method, suchas alignment bonding method. The adhesive layer 9 is aligned with thesecond surface 14 firstly, and then the adhesive layer 9 is adhered tothe second surface 14 by heating and pressing. The next step is todetach the growth substrate 81 from the semiconductor stack 1 and exposethe first surface 13 of the semiconductor stack 1. The method ofdetaching the growth substrate 81 comprises light irradiation method,such as laser lift-off, which utilizes laser to penetrate the growthsubstrate 81 and light the interface between the growth substrate 81 andthe semiconductor stack 1, and then the growth substrate 81 and thesemiconductor stack 1 are separated. The method of detaching the growthsubstrate 81 also comprises directly removing the growth substrate 81 bywet etching or removing the interface layer (not shown) between thesemiconductor stack 1 and the growth substrate 81. Besides, theinterface layer (not shown) between the semiconductor stack 1 and thegrowth substrate 81 can also be directly removed by using vapor to etchin high temperature to separate the growth substrate 81 and thesemiconductor stack 1.

Next, a portion of the second side 16 of the semiconductor stack 1 isremoved by wet etching or dry etching to form a vacancy 161 and expose aportion of the second extending portion 51, and the first surface 13 islithographically etched such that the first surface 13 has multipleprotrusion portions 131 and multiple concave portions 132 alternatelyarranged, wherein each protrusion portion 131 comprises a plateau 1313and at least one bevel 1312, and an inclined angle θ between 15 and 75degrees is formed between the bevel 1312 and the bottom surface of theconcave portion 132. Then at least one contacting structure 2 arrangedon the each protrusion portion 131 for ohmically contacting the firstsemiconductor layer 11. In the embodiment, the material of thecontacting structure 2 comprises Ge, Be, Au, Ni, Pd, Zn or the alloythereof.

As FIG. 4C shows, a transparent conduction layer 3 and a first extendingportion 41 are sequentially and conformally formed on the first surface13, wherein the transparent conduction layer 3 comprises ITO, InO, SnO,CTO, ATO, AZO, ZTO, ZnO or GaP, and the first extending portion 41comprises metal with high reflectivity, such as Ag, Au, Al, Ni, Sn, Cu,Ti, Pt and the alloy thereof. Then a first insulating layer 61 is formedon the first extending portion 41 to cover the first extending portion41 and the second side 16 of the semiconductor stack 1 and expose aportion of the first extending portion 41 above the first side of thesemiconductor stack 1, wherein the first insulating layer 61 fills aconcave-convex surface 411 of the first extending portion 41 while theconcave-convex surface 411 is formed by the first extending portion 41being conformal to the first surface 13.

Then, as FIG. 4D shows, the next step is forming a first connectingportion 42, a first bonding portion 43, a second connecting portion 52and a second bonding portion 53, wherein the second connecting portion52 and the second bonding portion 53 are formed on the first insulatinglayer 61, the first connecting portion 42 is formed on the first side 15of the semiconductor stack 1 for connecting the first extending portion41 and the first bonding portion 43, and the second connecting portion52 is formed on the vacancy 161 for connecting with the second bondingportion 53 and the exposed portion of the second extending portion 51.The material of the first connecting portion 42, the first bondingportion 43, the second connecting portion 52, and the second bondingportion 53 comprises Ti, W, Pt, Ni, Sn, Au or the alloy thereof.

Fourth Embodiment

FIG. 8A shows a structure of a semiconductor light-emitting device IV inaccordance with the fourth embodiment of the application. Thesemiconductor light-emitting device disclosed by the embodiment is aflip-chip type of light-emitting diode device with a reflector. Thesemiconductor light-emitting device comprises a semiconductor stack 1having a first surface 13 and a second surface 14 opposite to the firstsurface 13. The semiconductor stack 1 comprises a first semiconductorlayer 11, a second semiconductor layer 12, and an active layer 10between the first semiconductor layer 11 and the second semiconductorlayer 12, wherein the first surface 13 is the surface of the firstsemiconductor layer 11 and the second surface 14 is the surface of thesecond semiconductor layer 12. The first semiconductor layer 11 and thesecond semiconductor layer 12 have different electrically conductivetypes, electrical properties, polarities or provide electric holes orelectrons by being doped with different elements; the active layer 10between the first semiconductor layer 11 and the second semiconductorlayer 12 is capable of transforming electrical energy into light energy.The wavelength of the light from the active layer 10 can be adjusted bychanging the physical and chemical composition of one or multiple layersof the semiconductor stack 1. The commonly used material for forming thesemiconductor stack 1 comprises aluminum gallium indium phosphide(AlGaInP) series, aluminum gallium indium nitride (AlGaInN) or zincoxide (ZnO) series. The active layer 10 can be a single heterostructure(SH), double heterostructure (DH), double-side double heterostructure(DDH), multi-quantum well (MWQ) structure. Specifically, the activelayer 10 can be intrinsic, p-type or n-type semiconductor. When theelectrical current flows through the semiconductor stack 1, the activelayer 10 is capable of emitting light. As the material of the activelayer 10 is aluminum gallium indium phosphide (AlGaInP) series, theactive layer 10 is capable of emitting red, orange, yellow or amberlight; as the material of the active layer 10 is aluminum gallium indiumnitride (AlGaInN), the active layer 10 is capable of emitting blue orgreen light. In the following embodiment, the material of the activelayer 10 is aluminum gallium indium phosphide (AlGaInP) series.

A transparent conduction layer 3 is on the first surface 13 of the firstsemiconductor layer 11 to cover the first surface 13. The material ofthe transparent conduction layer 3 comprises ITO, InO, SnO, CTO, ATO,AZO, ZTO, ZnO, or GaP.

A first electrode 4 is formed on the first surface 13. The firstelectrode 4 comprises a first extending portion 41, a first bondingportion 43, and a first connecting portion 42. The first connectingportion 42 is on a first side 15 of the semiconductor stack 1 forconnecting the first extending portion 41 and the first bonding portion43, wherein the first extending portion 41 conformally covers andohmically contacts the transparent conduction layer 3. The firstextending portion 41 is made of metal with high reflectivity forreflecting the light emitted from the active layer 10 to exit from thesecond surface 14 of the second semiconductor layer 12. A firstinsulating layer 61 is on the first extending portion 41 to cover aportion of the first extending portion 41 and extend to cover the secondside 16 of the semiconductor stack 1. The first connecting portion 42 ison a portion of the first extending portion 41 which is uncovered by thefirst insulating layer 61 and directly contacts the first extendingportion 41. The first bonding portion 43 is on the first connectingportion 42. In the embodiment, the area of the first bonding portion 43is smaller than the area of the first connecting portion 42, and thematerial of the first bonding portion 43 is different from the materialof the first connecting portion 42. The material of the first bondingportion 43 and the first connecting portion 42 comprises Ti, W, Pt, Ni,Sn, Au or the alloy thereof; the first extending portion 41 comprisesmetal with high reflectivity, such as Ag, Au, Al, Ni, Sn, Cu, Ti, Pt,stacks thereof or the alloy thereof; the material of first insulatinglayer 61 comprises organic material, such as Sub, BCB, PFCB, epoxy,acrylic resin, COC, PMMA, PET, PC, polyetherimide and FluorocarbonPolymer; inorganic material, such as silicone and glass; dielectricmaterial, such as Al₂O₃, SiN_(x), SiO₂, TiO₂, and MgF₂. Multiplecontacting structures 54 are on the second surface 14 of thesemiconductor stack 1 and ohmically contact the second semiconductorlayer 12. An adhesive layer 9 is on the second surface 14 and covers allof the multiple contacting structures 54. The adhesive layer 9 comprisesa first adhesive layer 91 and a second adhesive layer 92, wherein thefirst adhesive layer 91 directly contacts the multiple contactingstructures 54 and the second surface 14 and protrudes from the firstside 15 or the second side 16 of the semiconductor stack 1. The secondadhesive layer 92 is arranged on the first adhesive layer 91 and adheresto the first adhesive layer 91. The material of the multiple contactingstructures 54 comprises Au, Ge, Be, Ni, Pd, Zn or the alloy thereof. Thefirst adhesive layer 91 is made of transparent and electricallyconductive material which comprises ITO, InO, IZO, SnO, CTO, ATO, AZO,ZTO, ZnO, or GaP. The second adhesive layer 92 is made of the materialwhich has good adhesion and transparent to the light emitted from theactive layer 10, wherein the material of the second adhesive layer 92comprises organic material, such as Sub, BCB, PFCB, epoxy, acrylicresin, COC, PMMA, PET, PC, polyetherimide and Fluorocarbon Polymer; orinorganic material, such as silicone.

A second electrode 5 comprises a second connecting portion 52 and asecond bonding portion 53. The second connecting portion 52 on the firstinsulating layer 61 covers a portion of the first surface 13, extends tocover the second side 16 and directly contacts the first adhesive layer91, wherein the first insulating layer 61 is able to prevent the secondconnecting portion 52 from directly contacting the first extendingportion 41, the transparent conduction layer 3 and the semiconductorstack 1. The second bonding portion 53 is arranged on the first surface13 and directly contacts the second connecting portion 52. The materialof the second connecting portion 52 and the second bonding portion 53comprises Ti, W, Pt, Ni, Sn, Au or the alloy thereof. The first bondingportion 43 and the second bonding portion 53 are used for importing theelectrical current to make the active layer 10 emitting a light. As thefirst semiconductor layer 11 is a p-type semiconductor and the secondsemiconductor layer 12 is an n-type semiconductor, the electricalcurrent enters the first bonding portion 43, then is conducted anddistributed by the first connecting portion 42, the first extendingportion 41, and the transparent conduction layer 3, and uniformly entersthe semiconductor stack 1. And then, the electrical current is conductedby the multiple contacting structures 54 and the first adhesive layer 91to the second connecting portion 52 and the second bonding portion 53,and finally exits from the second bonding portion 53.

In another embodiment, the surface 531 of the second bonding portion 53and the surface 431 of the first bonding portion 43 are on the samehorizontal plane. There is a gap 7 between the second bonding portion 53and the first bonding portion 43 to separate second bonding portion 53and the first bonding portion 43, wherein the width of the gap 7 isbetween 70 μm and 250 μm. As the shape of the semiconductorlight-emitting device is a square with four 12 mil sides and the area ofthe semiconductor light-emitting device is 144 square mil, the totalarea of the first bonding portion 43 and the second bonding portion 53is between 15%˜80% of the area of the semiconductor light-emittingdevice, and, in other words, the total area of the first bonding portion43 and the second bonding portion 53 is between 21.6 and 115.2 squaremil. As the shape of the semiconductor light-emitting device is a squarewith four 28 mil sides and the area of the semiconductor light-emittingdevice is 784 square mil, the total area of the first bonding portion 43and the second bonding portion 53 is between 60%˜92% of the area of thesemiconductor light-emitting device, and, in other words, the total areaof the first bonding portion 43 and the second bonding portion 53 isbetween 470.4 and 721.28 square mil. As the shape of the semiconductorlight-emitting device is a square with four 40 mil sides and the area ofthe semiconductor light-emitting device is 1600 square mil, the totalarea of the first bonding portion 43 and the second bonding portion 53is between 75%˜95% of the area of the semiconductor light-emittingdevice, and, in other words, the total area of the first bonding portion43 and the second bonding portion 53 is between 900 and 1520 square mil.

A substrate 8 is adhered to the second surface 14 by using the adhesivelayer 9, and the light emitted from the active layer 10 is able topenetrate the substrate 8 and the adhesive layer 9. The material of thesubstrate 8, which is transparent to the light emitted from the activelayer 10, comprises GaAs, GaP, GaN, sapphire, diamond, glass, quartz,acryl, ZnO or MN. In the embodiment, the first adhesive layer 91 is IZO(the refractive index is about 2.1), the second adhesive layer 92 is BCB(the refractive index is about 1.5), and the substrate 8 is glass (therefractive index is smaller than 1.5). As the light emitted from theactive layer 10 sequentially passes through the first adhesive layer 91,the second adhesive layer 92, and the substrate 8, since the refractiveindices decreases sequentially, the chance of total internal reflectioncan be reduced.

FIG. 8B shows the top-view of the structure of the semiconductorlight-emitting device IV in accordance with the fourth embodiment of theapplication. The width of the semiconductor stack 1 is smaller than thewidth of the substrate 8, and the multiple contacting structures 54 arearranged on the second surface 14 of the semiconductor stack 1 as anarray, wherein the multiple contacting structures 54 are independent anddo not contact to each other.

FIG. 7 shows a structure in accordance with another embodiment of theapplication. A light bulb 600 comprises a lampshade 602, a lens 604, alight module 610, a holder 612, a heat sink 614, a connector 616 and anelectrical connecting unit 618. The light module 610 comprises a carrier606 and a plurality of above-mentioned semiconductor light-emittingdevices 608 on the carrier 606.

Although the present application has been explained above, it is not thelimitation of the range, the sequence in practice, the material inpractice, or the method in practice. Any modification or decoration forpresent application is not detached from the spirit and the range ofsuch.

What is claimed is:
 1. A method of forming a semiconductorlight-emitting device, comprising: providing a semiconductor stack foremitting a light and having a first surface and a second surfaceopposite to the first surface, wherein the first surface comprisesmultiple protrusion portions and multiple concave portions; providing afirst electrode on the first surface and electrically connecting withthe semiconductor stack; providing a second electrode on the firstsurface and electrically connecting with the semiconductor stack;providing a transparent layer covering the first surface and between thefirst electrode and the semiconductor stack; and providing a transparentsubstrate on the second surface; wherein the light penetrates thetransparent substrate, wherein the first electrode comprises a firstbonding portion and a first extending portion, and the first extendingportion is between the first bonding portion and the transparent layerand covers the transparent layer, and wherein the protrusion portion isbetween 500 nm and 5000 nm in height.
 2. The method according toaccording to claim 1, further comprising providing an insulating layercovering the first extending portion and a first side of thesemiconductor stack, wherein the insulating layer is between the firstextending portion and the first bonding portion.
 3. The method accordingto claim 2, wherein the first electrode further comprises a firstconnecting portion passing through the insulating layer and electricallyconnecting the first bonding portion and the first extending portion. 4.The method according to claim 3, wherein the first connecting portion ison the second side of the semiconductor stack opposite to the firstside.
 5. The method according to claim 3, wherein the first bondingportion and the first connecting portion comprise a first material, thefirst extending portion comprises a second material, the first materialcomprises Ti, Pt, Ni, Sn, Au or the alloy thereof, and the secondmaterial comprises Ag, Au, Al, Ni, Sn, Cu, Ti, Pt or the alloy thereof.6. The method according to claim 1, wherein the protrusion portioncomprises a plateau and a bevel, the concave portion comprises a bottomsurface, and an angle between the bevel and the bottom surface isbetween 15 and 75 degrees.
 7. The method according to claim 1, whereinthe second electrode comprises a second bonding portion and a secondextending portion, wherein the second bonding portion is on the firstsurface and the second extending portion is on the second surface. 8.The method according to claim 7, wherein the second bonding portion andthe first bonding portion have the same area.
 9. The method according toclaim 7, wherein the total area of the first bonding portion and thesecond bonding portion is between 15% and 95% of the area of thesemiconductor light-emitting device.
 10. The method according to claim7, further comprising providing an insulating layer on the firstsurface, wherein the insulating layer is between the semiconductor stackand the second bonding portion.
 11. The method according to claim 10,wherein the second electrode further comprises a second connectingportion electrically connecting the second bonding portion and thesecond extending portion, and the second electrode is on a first side ofthe semiconductor stack, wherein the insulating layer is between thesecond connecting portion and the semiconductor stack.
 12. The methodaccording to claim 11, wherein the second extending portion comprisesAu, Be, Ge, Ni, Pd, Zn, or the alloy thereof.
 13. The method accordingto claim 11, wherein the second extending portion comprises ITO, InO,SnO, CTO, ATO, AZO, ZTO, or ZnO.
 14. The method according to claim 11,wherein the second bonding portion and the second connecting portioncomprise a fourth material and the fourth material comprises Ti, W, Pt,Ni, Sn, Au or the alloy thereof.
 15. The method according to claim 7,wherein the second extending portion comprises multiple extendingelectrodes which are parallel to each other corresponding to themultiple concave portions, and the multiple protrusion portions do notoverlap with the multiple extending electrodes in the directionperpendicular to the stacking direction.
 16. The method according toclaim 15, wherein the second surface comprises multiple concaves and themultiple extending electrodes are in the multiple concaves respectively.17. A method of forming a semiconductor light-emitting device,comprising: providing a semiconductor stack for emitting a light andhaving a first surface and a second surface opposite to the firstsurface; lithographically etching the first surface to form multipleprotrusion portions and multiple concave portions; providing multiplecontacting structures on the multiple protrusion portions and ohmicallycontacting the semiconductor stack; providing a first electrode on thefirst surface and ohmically contacting the multiple contactingstructures; providing a second electrode on the first surface andelectrically connecting with the semiconductor stack; providing atransparent layer to cover the first surface and between the firstelectrode and the semiconductor stack; and adhering a transparentsubstrate on the second surface; wherein the multiple contactingstructures comprise Au, Be, Ge, Ni, Pd, Zn or the alloy thereof, whereinthe light penetrates the transparent substrate, and wherein the firstelectrode comprises a first bonding portion and a first extendingportion, and the first extending portion is between the first bondingportion and the transparent layer and covers the transparent layer. 18.The method according to claim 17, wherein the protrusion portioncomprises a plateau and a bevel, the concave portion comprises a bottomsurface, and an angle between the bevel and the bottom surface isbetween 15 and 75 degrees.
 19. The method according to claim 17, furthercomprising forming an insulating layer to cover the first extendingportion and a first side of the semiconductor stack, wherein insulatinglayer is between the first extending portion and the first bondingportion.
 20. The method according to claim 19, wherein the firstelectrode further comprises a first connecting portion passing throughthe insulating layer and electrically connecting the first bondingportion and the first extending portion.